How do I reset my keyboard Shortcuts?
This shouldn't affect anything if you're clicking directly on buttons but you can use CtrlAltU to bring up your user preferences or press Space and search for it there. Next go to the Input tab and look for a button next to Window marked Restore (Blender remembers what changes you make and offers a handy way to reset only that section without messing up any other keybindings you remapped). From there you can use to set it back to the default value of whatever config preset you are using.

If you have nothing to lose you can also bring up the space menu and type load factory settings then save that as your new startup settings.